LICE AFFECTING GRAIN IN 1907 AND 1908 

 WITH NOTES ON INSECTARY WORK. 



THE SPRING GRAIN APHIS, OR THE SO-CALLED "'GREEN 



BUG." 



Toxoptcra (jraiiiimnii Rond. 



The year 1907 was made memorable by the "Green Bug Scare," 

 founded on a substantial basis in the South and a few of the south- 

 western states, but entirely uncalled for in Minnesota, where, though 

 the species was found well distributed over the state, it did no damage. 

 Nevertheless so great was the excitement caused by exaggerated, and, 

 in some instances, manufactured reports, and so often was a common 

 grain aphis (Macrosiphnni granaria) confused with this southern in- 

 sect that it was deemed expedient to make a special report to the 

 Governor ui)on this and other grain aphids. This was done, and 

 was issued in printed form in Alarch, 1908. Illustrated with colored 

 plates and fine drawings, showing not only the green bug and other 

 lice which resembled them, but also its chief parasite, this report was 

 intended to familiarize our farmers and others with the appearance 

 of this insect, and to allay any fears which ma}- have been caused by 

 exaggerated statements. 



The report was extensively circulated, and to spread the infor- 

 mation still further, it was later reproduced as Bulletin 108 from the 

 Experiment Station. In this bulletin the work of this department, as 

 far as it related to the green bug, was sununarized as follows: 



"The unusually mild winter and cool spring of 1907 in the 

 southern states, enabling the 'green bug" to multiply without inter- 

 ruption from its ])arasite, were the causes of the outbreak last season 

 in the South. ^Minnesota has long, cold winters and warm summers. 

 The first factor renders it impossible for this pest to multiply in 

 the winter or early spring as it does in parts of the South. The 

 second factor is favorable for the ra])id increase of its prineipal 

 parasite, which is found in this state, and which even in the South, 

 in ordinary years, keeps the pest in check. Therefore, in all prob- 

 ability, the Northwest will never have cause to fear an outbreak of 

 the 'green bug' or any other louse afifecting grain." 



